A network is a connection of two or more computers. The World Wide Web is different from the Internet. There are different types of networks, such as Local Area Network (LAN), which connects devices within a limited area, and Wide Area Network (WAN), which spans a larger geographical area. Wireless Local Area Network (WLAN) uses wireless technology to connect devices, while Personal Area Network (PAN) connects devices within a person's immediate proximity. Virtual Private Network (VPN) allows remote users to access a private network securely, and Storage Area Network (SAN) provides access to high-speed storage devices for storing large amounts of data.
Outline the importance of standards in the construction of networks
Describe how communication over networks is broken down into different layers.
The OSI (Open Systems Interconnection) Seven Layer Model is a theoretical model that explains how data is transmitted between networked devices. It consists of seven layers - Physical, Data Link, Network, Transport, Session, Presentation, and Application. The Physical layer is responsible for transmitting and receiving raw bitstreams, while the Data Link layer ensures reliable data transfer between adjacent nodes. The Network layer routes data between different networks, and the Transport layer provides reliable end-to-end communication between applications. The Session layer manages communication sessions between applications, and the Presentation layer represents data in a format that can be understood by applications. The Application layer is responsible for providing application services to users, including protocols and services that support applications like email, file transfer, and web browsing.
Identify the technologies required to provide a VPN.
To provide a VPN, the main components required are a VPN client, VPN server, VPN protocol, authentication, and encryption. The VPN client establishes the encrypted connection to the remote server, while the VPN server decrypts the traffic from the client and encrypts the traffic sent back to the client. Common VPN protocols include OpenVPN, IKEv2, and L2TP/IPsec, and authentication is done using a username and password, digital certificates, or other methods. Encryption is used to protect data transmission between the client and the server. VPNs use a process called tunnelling to encapsulate and encrypt data, creating a new packet that contains the original data and transmitting it through a tunnel between two devices. The process involves encapsulating the data, encrypting the packet, transmitting it through the tunnel, and decrypting the packet at the destination. Tunnelling adds an extra layer of security, making it more challenging for attackers to intercept and access sensitive information transmitted over an insecure network.
Evaluate the use of a VPN
A VPN, or Virtual Private Network, allows users to create a secure and encrypted connection between their device and a remote server over the internet, creating a private network that enables secure and anonymous access to the internet and other resources, especially on public Wi-Fi networks. The advantages of using a VPN include improved security, privacy, access to restricted content, remote access, and cost savings. By encrypting internet traffic and hiding users' IP addresses, a VPN provides a secure and private connection to the internet, regardless of location or network used.
DATA TRANSMISSION | FLIP CARDS
Define the terms: protocol, data packet.
A protocol is a set of rules and procedures that govern the communication between devices and the operation of computer networks. Protocols provide a standardized way for devices to communicate with each other, ensuring compatibility, efficiency, reliability, and security.
Packet switching is a technique for transmitting data over a network by breaking it down into smaller units called packets. Each packet contains a portion of the data, along with a header that contains information about the packet, such as its source and destination addresses. When the packets are transmitted, they may take different routes to reach their destination, and at the receiving end, the packets are reassembled into the original data. Packet switching allows for efficient and reliable data transmission by optimizing network resources and ensuring data integrity.
Explain why protocols are necessary
Protocols are essential for the operation of computer networks as they provide standardized rules and procedures for transmitting data over a network. They ensure compatibility, efficiency, reliability, security, and innovation in network communication. To maintain data integrity, protocols provide techniques like error checking and redundancy. Flow control is necessary to manage the rate of data transmission to prevent overload or congestion on a network. Deadlock occurs when multiple devices compete for the same resources, and congestion arises when the traffic on a network exceeds its capacity. Lastly, error checking techniques like checksums, parity bits, and cyclic redundancy checks are used to detect and correct errors in data transmission to ensure data integrity.
Explain why the speed of data transmission across a network can vary.
The speed of data transmission over a network can change due to factors such as bandwidth limitations, network congestion, distance, network type, and the performance of network devices. These factors can cause delays and slower speeds during peak usage times or when data is transmitted over longer distances. Network administrators can optimize network performance by understanding these factors and taking appropriate measures to ensure efficient data transmission.
Explain why compression of data is often necessary when transmitting across a network
Data compression is important for transmitting data across a network, as it can reduce the amount of data that needs to be transmitted, resulting in faster transmission times, more efficient use of network resources, and cost savings. Compression can optimize bandwidth and storage, improve the user experience, and save costs on network infrastructure and connectivity. Lossless or lossy compression techniques can be used to compress data.
Outline the characteristics of different transmission media.
There are three main mediums used for data transmission over networks - optical cable, copper cable, and wireless. Copper cable is divided into two main types - coaxial cable and twisted pair. Twisted pair cables are widely used in local area networks due to their low cost and robustness, while optical cables are used for long-distance data transfer due to their fast transfer rates. Coaxial cables are less common due to their lower cost for performance ratio and susceptibility to hacking and damage
Explain how data is transmitted by packet switching
Data transmission involves sending information from one device to another over a network by breaking it down into smaller units called packets. Each packet contains a portion of the data along with a header that contains information about the packet, such as its source and destination addresses and the sequence number. The packets are transmitted individually and may take different routes to reach their destination. At the receiving end, the packets are reassembled into the original data, and the header information is used to ensure that the packets are received in the correct order and to check for any errors or lost packets during transmission. Packet structure consists of a header, payload, and trailer. Packet switching is the process of transmitting data over a network by breaking it down into small units called "packets", routing each packet independently, and reassembling the packets at the destination to form the original data.
Another type of data transfer is called 'Circuit Switching'
WIRELESS NETWORKING | FLIP CARDS
Outline the advantages and disadvantages of wireless networks.
Wireless networks offer advantages such as mobility, cost-effectiveness, convenience, scalability, and accessibility. However, they also have disadvantages such as security concerns, interference, limited range, potential speed and performance issues, and compatibility limitations. To mitigate these drawbacks, businesses and organizations must implement appropriate security measures, carefully consider network design and hardware, and assess whether a wireless network is the right choice for their specific needs.
Describe the hardware and software components of a wireless network
A wireless network comprises hardware and software components that function together to provide wireless connectivity and access to network resources. The hardware components include Wireless Access Points (WAPs), Network Interface Cards (NICs), routers, and switches. The software components include the Operating System (OS), network protocols, wireless network management software, and network security software. By properly configuring these components, businesses and organizations can establish a wireless network that is secure, reliable, and efficient to cater to their needs.
Describe the characteristics of wireless networks
Wireless networks are characterized by their mobility, convenience, scalability, interference, security, speed and performance, and range limitations. It is crucial for businesses and organizations to consider these characteristics when selecting and implementing a wireless network that aligns with their needs and requirements. Mobility: Wireless networks provide greater mobility and flexibility than wired networks as users can connect to the network from anywhere within range of the wireless signal.
Convenience: Wireless networks are more convenient to use than wired networks, as users can connect to the network without the need for physical cables or connectors.
Scalability: Wireless networks can be easily expanded and scaled to meet the changing needs of a business or organization.
Interference: Wireless signals can be subject to interference from other devices or networks, which can impact the performance and reliability of the network.
Security: Wireless networks can be less secure than wired networks as wireless signals can be intercepted and accessed by unauthorized users, making it essential to implement security measures such as encryption and authentication to protect the network.
Speed and performance: Wireless networks may not provide the same speed and performance as wired networks, particularly for data-intensive applications such as video streaming or large file transfers.
Range limitations: Wireless networks have a limited range, which means that they may not be suitable for larger buildings or areas where multiple access points are required.
Describe the different methods of network security.
To protect wireless networks from security threats, various methods can be used, including encryption, authentication, access control, firewalls, intrusion detection and prevention systems, and network monitoring and management tools. These methods aim to prevent unauthorised access to the network, protect sensitive data, and monitor network traffic for potential security threats. However, each method has its own advantages and disadvantages, and businesses and organizations should carefully consider which methods are best suited for their specific security needs.
Evaluate the advantages and disadvantages of each method of network security.
ENCRYPTION ADVANTAGES
Provides a high level of security by encoding the data so that it can only be read by authorized users
Supports various encryption methods such as WEP, WPA, and WPA2
Easy to implement on most wireless networks
ENCRYPTION DISADVANTAGES
Older encryption methods such as WEP are vulnerable to attacks and should not be used
Encryption can increase the processing overhead and reduce network performance
Keys and passwords must be managed and updated regularly to ensure security
AUTHENTIFICATION ADVANTAGES
Provides a way to verify the identity of users who access the wireless network
Can be used in combination with encryption for added security
Supports various authentication methods such as passwords, digital certificates, and biometric authentication
AUTHENTIFICATION ADVANTAGES
Authentication can be vulnerable to attacks such as password cracking and phishing
Strong authentication methods such as biometric authentication can be expensive to implement
Authentication methods must be managed and updated regularly to ensure security
ACCESS CONTROL ADVANTAGES
Provides a way to limit access to the network and its resources to authorized users
Can be used to prevent unauthorized access to the network, such as using MAC address filtering, network segmentation, and virtual private networks (VPNs)
Easy to implement on most wireless networks
ACCESS CONTROL ADVANTAGES
Access control mechanisms can be vulnerable to attacks such as MAC address spoofing
Access control policies can be difficult to manage and update, particularly in large networks
Access control mechanisms can be complex to configure and troubleshoot
FIREWALL ADVANTAGES
Provides a way to monitor and control network traffic between the network and the internet
Can be used to block unauthorized access to the network, prevent malware and virus attacks, and protect sensitive data
Can be configured to allow or block traffic based on various criteria such as IP address, port, and protocol
FIREWALL ADVANTAGES
Firewalls can be expensive to implement, particularly for large networks
Firewalls can increase network latency and reduce network performance
Firewalls must be configured and maintained carefully to ensure that they do not block legitimate traffic
INTRUSION DETECTION AND PREVENTION SYSTEMS ADVANTAGES
Provides a way to monitor network traffic and identify potential security threats
Can be used to prevent attacks by blocking suspicious traffic, such as Denial of Service (DoS) attacks
Can be configured to provide alerts, reporting, and analysis of network activity
INTRUSION DETECTION AND PREVENTION SYSTEMS ADVANTAGES
Intrusion detection and prevention systems can be expensive to implement, particularly for large networks
Intrusion detection and prevention systems can increase network latency and reduce network performance
Intrusion detection and prevention systems must be configured and maintained carefully to avoid false positives and false negatives
NETWORK MONITORING AND MANAGEMENT ADVANTAGES
Provides a way to identify and respond to security threats in real-time
Can be used to provide alerts, reporting, and analysis of network activity
Can be used to optimize network performance and troubleshoot problems
NETWORK MONITORING AND MANAGEMENT ADVANTAGES
Network monitoring and management tools can be expensive to implement, particularly for large networks
Network monitoring and management tools can increase network latency and reduce network performance
Network monitoring and management tools must be configured and maintained carefully to avoid false positives and false negatives
